RB1 and neoplasm: To corroborate the bioinformatic signatures of DNA damage, we stained normal kidneys from 10 non-Cre mice and 92 Vhl/Trp53/Rb1-deficient mouse ccRCCs from 16 mice with an antibody against the double-strand break DNA damage marker γ-H2AX and quantified the percentage of positively stained nuclei per tumor or region of normal cortex.